KR20110126601A - Method for measuring external shape of rectangular plate-like object, and method for calibrating relative position of image-capturing means - Google Patents

Abstract

The external shape of the rectangular plate-shaped object conveyed is measured using the shape measuring apparatus provided with the four imaging means arrange | positioned corresponding to the four corners of a rectangular plate-shaped object beforehand, and the storage means for storing the relative coordinates of each of the said four imaging means. An image comprising a step of determining whether or not the rectangular plate-like article has reached the measurement section, and a corner portion of each of the four corners of the rectangular plate-shaped article reaching the measurement section by the four imaging means. A step of imaging, a step of calculating corner post coordinates which are coordinate values from an image origin of each of the four corners of the rectangular plate-shaped object based on the picked-up image, the calculated corner post coordinates and the relative stored in the storage means Based on the coordinates, the length dimension of each of the four sides of the rectangular plate-like object and the squareness of each of the four corners are opened. A step of dispersing is provided.

Description

METHOD FOR MEASURING EXTERNAL SHAPE OF RECTANGULAR PLATE-LIKE OBJECT, AND METHOD FOR CALIBRATING RELATIVE POSITION OF IMAGE-CAPTURING MEANS}

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a measuring method for measuring the external shape of a rectangular plate such as a glass plate (dimensions and squareness of four corners, etc.), and in particular, the external shape of a rectangular plate such as a glass plate conveyed on a line (dimensions of a square and four corners). The measurement method which can measure non-stop non-stop) is related.

Conventionally, in the field of glass plates, such as glass plates for liquid crystal displays, glass plates for plasma displays, glass plates for field emission displays, and glass plates for flat display panels such as organic EL, external shapes of rectangular glass plates (dimensions and squareness of four corners, etc.) ), It is required to efficiently and efficiently measure non-contact in a short time and with high accuracy. As an apparatus complying with this request, the glass plate is imaged, and the external shape (dimensions and squareness of four corners) of the glass plate is based on the captured image and the like. And a shape measuring device for automatically measuring the size thereof is proposed (see, for example, Patent Document 1 below).

It is a front view of the shape measuring apparatus of patent document 1. It is a side view of the shape measuring apparatus of patent document 1.

As shown to FIG. 10, FIG. 11, the shape measuring apparatus 100 of patent document 1 is the X-axis guide 102 extended in the X-axis direction, and the Y-axis guide 104 extended in the Y-axis direction, The imaging means 106 and the motor (not shown) etc. which move the imaging means 106 to an XY direction along the X-axis and Y-axis guides 102 and 104 are provided.

In this shape measuring apparatus 100, as shown in FIG. 11, carrying in the inclined posture, the edge of the glass plate 110 supported on the test stand 108, etc., moving the imaging means 106 to XY direction It picks up and automatically measures the external shape (dimensions, the squareness of four corners, etc.) of the glass plate 110 based on the image etc. which were taken.

Japanese Patent Laid-Open No. 2007-205724

However, since this shape measuring apparatus 100 is a structure which image | photographs the edge of the glass plate 110 etc. using the imaging means 106 which moves to an XY direction, the said glass plate 110 is fixed on the test stand 108. It is necessary to fix the time, and the shape cannot be measured non-stop with respect to each of the some glass plates 110 conveyed on a line, measurement takes time, and a feedback to manufacturing conditions becomes slow at the time of a defect occurrence. For this reason, there exists a problem that a yield cannot be improved.

This invention is made | formed in view of such a situation, and an object of this invention is to provide the measuring method which can measure the external shape (dimensions and squareness of four corners, etc.) of rectangular plate-shaped objects, such as a glass plate conveyed on a line, nonstop. .

This invention uses the shape measuring apparatus provided with the four imaging means arrange | positioned previously corresponding to the four corners of a rectangular plate-shaped object, and the storage means which stores the relative coordinates of each of the said four imaging means in order to achieve the said objective. In the measuring method of measuring the external shape of the rectangular plate-shaped object conveyed so that it may pass through a shape measuring section, the step of determining whether the said rectangular plate-shaped object reached | attained the said measurement section, and the said rectangular plate-shaped object are the said measurement section In the case where it is determined that the image has been reached, the step of picking up an image including the corner portions of each of the four corners of the rectangular plate-like object that has reached the measurement section by the four imaging means, and based on the picked-up image, the rectangular plate shape Calculating corner post coordinates that are coordinate values from the image origin of each of the four corners of water; Calculating the length dimension of each of the four sides of the rectangular plate-shaped object based on the corner post coordinates of the rectangular plate-shaped object and the relative coordinates stored in the storage means, the calculated corner post coordinates, the relative coordinates stored in the storage means and the A method for measuring the external shape of a rectangular plate-shaped object, comprising the step of calculating the squareness of each of the four corners of the rectangular plate-shaped object on the basis of the calculated length dimension.

According to the above configuration, the corners of each of the four corners of the rectangular plate-like object are simultaneously (or almost simultaneously) by four imaging means arranged in advance corresponding to the four corners of the rectangular plate-shaped object without moving the imaging means in the XY direction as in the prior art. An image including a part is picked up, and based on the picked-up image or the like, an external shape (length dimension of each of the four sides of the rectangular plate-shaped object and the squareness of each of the four corners of the rectangular plate-shaped object) is calculated. For this reason, shape measurement can be performed non-stop about each of the some rectangular plate-shaped object conveyed on a line, and it becomes possible to improve a yield.

Moreover, the external shape measuring method of this invention further includes the step of comparing the calculated length dimension and orthogonality with a predetermined standard value, and the step of performing the defect determination of the external shape of the rectangular plate-shaped object based on the comparison result. You may provide it.

According to the said structure, the defect determination of the external shape of a rectangular plate-shaped object becomes possible.

In addition, the shape measurement method of the present invention is based on the pre-measured length dimension of each of the four sides of the standard rectangular plate-like product for calibration and the measured squareness of each of the four corners of the standard rectangular plate-like object for calibration. A step of correcting a previously measured squareness of each of the four corners of water, a step of photographing an image including the corner portions of each of the four corners of the standard rectangular plate-like object for calibration by the four imaging means, and the captured image. Calculating corner post coordinates of each of the four corners of the standard rectangular plate-shaped object for calibration, and the corner post coordinates of the calculated standard rectangular plate-shaped object, the corrected squareness and the standard rectangular plate-shaped object of calibration. Based on the measured length dimension of each of the sides, the relative coordinates of each of the four imaging means are calculated, You may further comprise the step of storing in a storage means.

According to the above configuration, the rectangular shape of the rectangular plate-shaped object (four rectangular plate-shaped objects) is obtained by using a standard rectangular plate for calibration in which the length dimension of each of the four sides and the squareness of each of the four corners are measured in advance. It becomes possible to calculate the relative coordinates of each of the four imaging means which are the basis of the calculation of the length dimension of each side and the squareness of each of the four corners of a rectangular plate-shaped object).

In addition, since a step for correcting the pre-measured squareness of each of the four corners of the rectangular plate-shaped object is provided, a measurement error occurs in the length dimension of each of the four sides of the standard rectangular plate-shaped object for calibration, and the squareness of each of the four corners. Even if it is included, the measurement error is canceled. This makes it possible to calculate the relative coordinates of each of the four imaging means more accurately.

Moreover, this invention is a standard rectangular plate shape for calibration in the method of calibrating the relative coordinates of the said four imaging means in the shape measuring apparatus provided with four imaging means arrange | positioned correspondingly to the four corners of a rectangular plate-shaped object beforehand. Correcting the measured squareness of each of the four corners of the rectangular plate-like based on the measured length dimension of each of the four sides of the water and the measured squareness of each of the four corners of the standard rectangular plate-shaped for calibration; Picking up an image including corner portions of each of the four corners of the standard rectangular plate-like object for calibration by the four imaging means, and corner posts of each of the four corners of the standard rectangular plate-like object for calibration, based on the picked-up image Calculating coordinates, the corner post coordinates of the calculated standard rectangular platelets, the corrected squareness and And providing a step of calculating relative coordinates of each of the four imaging means, based on a pre-measured length dimension of each of the four sides of the calibration standard rectangular plate-shaped object. do.

According to the above configuration, by using a standard rectangular plate for calibration in which the length dimension of each of the four sides and the squareness of each of the four corners are measured in advance, the length of each of the four sides of the rectangular plate is It becomes possible to calculate the relative coordinates of each of the four imaging means, which are the basis for the calculation of the dimensions and the squareness of each of the four corners of the rectangular plate-shaped object.

In addition, since a step for correcting the pre-measured squareness of each of the four corners of the rectangular plate-shaped object is provided, a measurement error occurs in the length dimension of each of the four sides of the standard rectangular plate-shaped object for calibration, and the squareness of each of the four corners. Even if it is included, the measurement error is canceled. This makes it possible to calculate the relative coordinates of each of the four imaging means more accurately.

As explained above, according to this invention, it becomes possible to provide the measuring method which can non-stop measure the external shape (dimensions and the squareness of four corners, etc.) of rectangular plate-shaped objects, such as a glass plate conveyed on a line.

FIG. 1: is a system block diagram of the shape measuring apparatus applied to the external shape measuring method of the rectangular plate-shaped object of this embodiment.
It is a figure for demonstrating the general manufacturing process of a glass plate.
3 is a plan view near the shape measuring section 32 on the measuring line 30.
4 is a view for explaining the positional relationship between four sides and a corner of the standard glass plate for calibration 36 and the imaging means 18C0 to 18C3.
5 is an example of the images P1 to P4 picked up by the respective imaging means 18C0 to 18C3.
6 is a flowchart for explaining a process of calculating the relative coordinates of each of the four imaging means 18C0 to 18C3.
Fig. 7 illustrates the relationship between the length dimensions E1, E2, ER, EL of each of the four sides of the calibration standard glass plate 36, and the right angles ∠1 to ∠4 of each of the four corners of the calibration standard glass plate 36. It is for the drawing.
FIG. 8 is a diagram for explaining the relationship between relative coordinates S0 to S3, approximate correction angles R1 *, R2 *, and the like of each of the four imaging means 18C0 to 18C3.
9 is a flowchart for explaining a method of measuring the external shape of the work glass plate 34.
It is a front view of the shape measuring apparatus of patent document 1.
It is a side view of the shape measuring apparatus of patent document 1.

EMBODIMENT OF THE INVENTION Hereinafter, preferred embodiment of the external shape measuring method of the rectangular plate-shaped object which concerns on this invention is described in detail based on an accompanying drawing.

FIG. 1: is a system block diagram of the shape measuring apparatus applied to the external shape measuring method of the rectangular plate-shaped object of this embodiment. It is a figure for demonstrating the general manufacturing process of a glass plate. 3 is a plan view near the shape measuring section 32 on the measuring line 30.

[Overview of shape measuring device]

As shown in FIG. 2, a glass plate generally wash | cleans with respect to the cutting process which cuts the plate glass manufactured by predetermined thickness to predetermined size, the chamfering process which performs a chamfering process with respect to the glass plate after cutting, and the glass plate after a chamfering process. -It manufactures through the washing | cleaning and drying process which performs drying, and the measuring process (measurement line) which measures the external shape of the glass plate after washing and drying.

The shape measuring apparatus 10 of this embodiment is an apparatus for measuring the external shape of a glass plate, and is provided in the shape measuring section 32 on the measurement line 30 as shown in FIG. The cleaned and dried glass plate 34 (for example, a rectangular glass plate having a length L (several m) x width W (several m) shown in Fig. 3) is hereinafter referred to as a work glass plate) known conveying means (not shown). Is conveyed on the measurement line 30 and passes through the shape measurement section 32. The shape measuring apparatus 10 automatically non-stops the external shape of the work glass plate 34 passing through the shape measuring section 32 (length dimension of each of the four sides of the work glass plate 34 and the squareness of each of the four corners). Measure

[Configuration of shape measuring device]

As shown in FIG. 1, the shape measuring apparatus 10 includes four lights connected to the image processing apparatus 12 and the image processing apparatus 12 through an LED power supply 14 and a predetermined interface (not shown). Four imaging means 18C0 to 18C3 connected to the means 16, an image processing apparatus 12 via a predetermined interface (not shown), and a connection to the image processing apparatus 12 via a predetermined interface (not shown). Sensor 20 and the like are provided.

The image processing apparatus 12 is provided with arithmetic and control means 12a such as an MPU and a CPU, a storage means 12b such as a RAM and a ROM, and the like. The image processing apparatus 12 controls the lighting means 16 and each imaging means 18C0 to 18C3 by the calculation / control means 12a executing a predetermined program read in the storage means 12b. And a calculation means for calculating the external shape of the work glass plate 34.

The illuminating means 16 is for illuminating four corners of the work glass plate 34, and is an illuminating device including a plurality of LED light sources (not shown) arranged in a ring shape, for example. As shown in FIG. 1, the illumination means 16 is arrange | positioned in four places corresponding to each of the four corners of the workpiece glass plate 34. As shown in FIG. The lighting means 16 lights up according to control from the image processing apparatus 12, and illuminates four corners of the workpiece glass plate 34. As shown in FIG.

The imaging means 18C0 to 18C3 are for imaging four corners of the work glass plate 34, and for example, imaging including an CCD or CMOS imaging device (for example, resolution: several tens of micrometers / pic). Device. In the imaging means 18C0 to 18C3, the corner portions C1 to C4 (see FIGS. 1, 3, 4, etc.) of each of the four corners of the work glass plate 34 have a viewing range (for example, a viewing range: several tens of mm ×). It is arrange | positioned in four places corresponding to each of the four corners of the workpiece glass plate 34 so that it may enter several tens of mm). The imaging means 18C0 to 18C3 image the images P1 to P4 including the corner portions C1 to C4 of the four corners of the work glass plate 34 under the control from the image processing apparatus 12. 5 is an example of the images P1 to P4 picked up by the respective imaging means 18C0 to 18C3. The captured images P1 to P4 are introduced into the image processing apparatus 12.

The sensor 20 is for detecting whether the workpiece glass plate 34 to be measured has reached the measurement section 32 (inside a predetermined imaging position), and is, for example, a photo interrupter. When the sensor 20 detects the edge edge 34a (edge) of the conveyance direction of the workpiece glass plate 34, it notifies the image processing apparatus 12 of the detection signal of the effect. The image processing apparatus 12 which received the said notification controls each illumination means 16 so that the four corners of the workpiece glass plate 34 which reached | attained the said measurement section 32 may be illuminated. In addition, each imaging means 18C0-18C3 is controlled so that the image containing the corner parts C1-C4 of each of the four corners of the said workpiece glass plate 34 may be imaged.

[Relative coordinate calculation processing using calibration standard glass plate (calibration method)]

Next, the process of calculating the relative coordinates of each of the four imaging means 18C0-18C3 using the standard glass plate for calibration is demonstrated, referring FIG. 6 is a flowchart for explaining a process of calculating the relative coordinates of each of the four imaging means 18C0 to 18C3. The following processing is realized by the image processing apparatus 12 (operation / control means) executing a predetermined program read in the storage means 12b or the like.

As shown in FIGS. 4 and 7, the length dimensions E1, E2, EF, and ER of each of the four sides of the standard glass plate for calibration 36 and the squareness of each of the four corners of the standard glass plate for calibration 36 are measured. To # 4 are previously measured using a calibration gauge such as a linear gauge, and stored in the storage means 12b or the like as shown in Table 1 below.

Right angle means the magnitude of the deviation from the right angle of each corner of each of the four corners of the standard glass plate 36 for calibration which should be right angle. In this embodiment, when it is assumed that the point on the said standard glass plate for correction | amendment 36 mm spaced from the corner parts C1 to C4 of each of the four corners of the standard glass plate 36 for correction, and the cabinet of each of the four corners are right angles, The distance (mm) of the point on the said calibration standard glass plate 36 separated 1000 mm from the corner parts C1-C4 of each of the four corners of the calibration standard glass plate 36 of was used as a squareness. In addition, the difference (rad) between the inner corners of each of the four corners of the standard glass plate for calibration 36 and the inner corners of each of the four corners of the standard glass plate for calibration (a right angle) is assumed to be a right angle. May be employed as the squareness.

However, these measurement values themselves (particularly, the rectangular angles # 1 to # 4) already include measurement errors (offset errors of the calibration gauges). This measurement error is canceled out, and the perpendicularity degrees # 1-# 4 are correct | amended so that the sum of the internal angles of the four corners of the calibration standard glass plate 36 may be four square angles (step S10).

Specifically, as shown in the following Table 2, Number 1, and Table 3, the right angles # 1 to # 4 are corrected.

In Table 2, DWSn ← n / 1000 is divided into variables DWS1 to DWS4 at right angles ∠1 to ∠4 divided by 1000mm, which is the distance between the right angle measurement point and the corner portions C1 to C4 of each of the four corners, ∠1 / 1000 to 내지 n / 1000. It indicates that # 4/1000 is substituted respectively. In Table 2, Rn #? ATAN (DWSn) indicates that the cabinets ATAN (DWS1 to DWS4) of the radiated (RADized) corner portions C1 to C4 are respectively substituted into the variables R1 # to R4 #.

In Table 2, aR ← (R1 # + R2 # + R3 # + R4 #) / 4.0 indicates that the average value of the radiated (RADized) cabinet ATAN (DWS1 to DWS4) is substituted into the variable aR. have. In Table 2, Rn ← Rn # -aR indicates that the values obtained by subtracting the variables aR from the variables R1 # to R4 # are substituted into the variables R1 to 4, respectively.

Thereby, an error is contained in the measured value of the cabinet of the calibration standard glass plate 36, and the sum R1 # + R2 # + R3 # + R4 # of the measured value of the cabinet of the calibration standard glass plate 36 becomes zero. Even if not, R1 + R2 + R3 + R4 becomes zero as follows.

R1 + R2 + R3 + R4 = (R1 # -aR) + (R2 # -aR) + (R3 # -aR) + (R4 # -aR)

= R1 # + R2 # + R3 # + R4 # -4 × aR

= 0

In the above processing, when at least one of | R3 + R4 |> 0.000001 or | AR12 |> 0.000001 is not satisfied, both R3 * and R4 * are zero. In addition, when at least one of | R1 + R2 |> 0.000001 or | AR12 |> 0.000001 is not satisfied, both R1 * and R2 * are zero.

Assuming that the standard glass plate for calibration 36 is a substantially parallelogram, the difference is the difference between the sums of the angles of both ends of the sides with which the sides of the sides are compared (which is 180 degrees in the case of the parallelogram). The difference is corrected for the difference between the length of the long side and the difference between the length of the short side so that the difference is proportionally distributed to the value of the original angle so as to reflect the difference of the length of the side in the squareness.

By this process, approximate correction angles R1 * to R4 * are calculated and stored in the storage means 12b.

The image processing apparatus 12 then controls each illumination means 16 to illuminate four corners of the calibration standard glass plate 36. At the same time, the respective imaging means 18C0 to 18C3 are controlled to image an image including corner portions C1 to C4 of each of the four corners of the calibration standard glass plate 36.

Each illumination means 16 lights up according to the control from the image processing apparatus 12, and illuminates four corners of the said standard glass plate 36 for calibration. In addition, each imaging means 18C0 to 18C3 captures images P1 to P4 including corner portions C1 to C4 of each of the four corners of the standard glass plate 36 for calibration according to control from the image processing apparatus 12. (Step S12). 5 is an example of the images P1 to P4 picked up by the respective imaging means 18C0 to 18C3. The captured images P1 to P4 are introduced into the image processing apparatus 12.

Subsequently, the image processing apparatus 12 performs corner post coordinates (hereinafter referred to as CP coordinates) which are mm converted coordinate values from the image origin of each of the four corners of the standard glass plate for calibration 36, based on the captured images P1 to P4. C1PX to C4PX, C1PY to C4PY, and corner cut dimensions (hereinafter referred to as CC dimensions) C1LX to C4LX, C1LY to C4LY are calculated (steps S14, S16).

For example, by performing predetermined image processing on each of the images P1 to P4, each edge (horizontal edge EH, vertical edge EV, inclination edge EB) is detected as shown in FIG. The intersection of EV and slope edge EB is obtained (step S14). Based on these intersections etc., CP coordinates C1PX to C4PX, C1PY to C4PY and CC dimensions C1LX to C4LX, C1LY to C4LY are calculated (step S16).

Subsequently, the image processing apparatus 12 is each of four sides of the calculated CP coordinates C1PX to C4PX, C1PY to C4PY, and the calibration standard glass plate 36 stored in the storage means 12b. Relative to each of the four imaging means 18C0 to 18C3 based on the pre-measured length dimensions E1, E2, ER, EL and the approximate correction angles R1 *, R2 *, R3 *, R4 * stored in the storage means 12b. The coordinates S0 to S3 are calculated and stored in the storage means 12b (step S18).

Specifically, the relative coordinates S0 to S3 of the four imaging means 18C0 to 18C3 are calculated using the equations shown in Table 4 below.

By the above process, the relative coordinates S0 to S3 of each of the four imaging means 18C0 to 18C3 are calculated and stored in the storage means 12b. FIG. 8 has shown the relationship of the relative coordinates S0 to S3 of each of the four imaging means 18C0 to 18C3, approximate correction angles R1 *, R2 *, and the like.

[Method of Measuring External Shape of Work Glass Plate]

Next, the method of measuring the external shape of the workpiece glass plate 34 conveyed so that it may pass through the shape measuring section 32 using the shape measuring apparatus 10 of the said structure is demonstrated, referring FIG. 9 is a flowchart for explaining a method of measuring the external shape of the work glass plate 34. The following processing is realized by the image processing apparatus 12 (operation / control means) executing a predetermined program read in the storage means 12b or the like. In addition, it is assumed that the relative means S0 to S3 of the four imaging means 18C0 to 18C3 are stored in advance in the storage means 12b. The stored relative coordinates S0 to S3 read previously stored relative coordinates S0 to S3 from the storage means 12b as long as the arrangement of the imaging means 18C0 to 18C3 is the same arrangement as before. It is possible. In other words, as long as the arrangement of the imaging means 18C0 to 18C3 is the same arrangement as before, the previously stored relative coordinates S0 to S3 can be reused, and it is not necessary to perform steps S10 to S18 each time.

First, the image processing apparatus 12 determines whether the workpiece glass plate 34 has reached the measurement section 32 (step S20). When the image processing apparatus 12 determines that the workpiece glass plate 34 to be measured has reached the measurement section 32 (the predetermined imaging position in the step) (step S20: YES), that is, the workpiece 20 from the sensor 20. When receiving the notification of the detection signal that the edge edge 34a (edge) in the conveyance direction of the glass plate 34 is detected, each corner is illuminated so as to illuminate four corners of the work glass plate 34 that have reached the measurement section 32. Control the lighting means 16. In addition, each imaging means 18C0-18C3 is controlled so that the image containing the corner parts C1-C4 of each of the four corners of the said workpiece glass plate 34 may be imaged.

Each lighting means 16 lights up according to control from the image processing apparatus 12, and illuminates four corners of the said workpiece glass plate 34. As shown in FIG. Further, each imaging means 18C0 to 18C3 includes images p1 to p4 including corner portions C1 to C4 of each of the four corners of the work glass plate 34 under control from the image processing apparatus 12 (in FIG. 5). An image similar to the illustrated images P1 to P4) is captured (step S22). The captured images p1 to p4 are introduced into the image processing apparatus 12.

Subsequently, the image processing apparatus 12 has CP coordinates c1Px to c4Px, c1Py to c4Py and CC dimensions c1Lx to c4Lx and c1Ly to c4Ly based on the captured images p1 to p4, respectively. Is calculated (steps S24, S26).

For example, by performing predetermined image processing on each of the images p1 to p4, as shown in Fig. 5, each edge (horizontal edge EH, vertical edge EV, inclination edge EB) is detected and horizontal and vertical edges are detected. The intersection of EH, EV, and the inclined edge EB is obtained (step S24). Based on these intersections, CP coordinates c1Px to c4Px, c1Py to c4Py, and CC dimensions c1Lx to c4Lx, c1Ly to c4Ly are calculated (step S26).

Next, the image processing apparatus 12 is based on the calculated CP coordinates c1Px to c4Px, c1Py to c4Py and the relative coordinates S0 to S3 stored in the storage means 12b of the work glass plate 34. The length dimensions E1, E2, ER, and EL for each of the four sides of S are calculated and stored in the storage means 12b (step S28).

Specifically, length dimensions E1, E2, ER, and EL of each of the four sides of the work glass plate 34 are calculated using the equation described below.

By the above process, length dimension E1, E2, ER, EL of each of four sides of the workpiece glass plate 34 is computed, and is stored in the memory | storage means 12b.

Subsequently, the image processing apparatus 12 is based on the calculated CP coordinates c1Px to c4Px, c1Py to c4Py, the relative coordinates S0 to S3 stored in the storage means 12b, and the calculated length dimensions E1, E2, ER, EL. Then, the squareness # 1-# 4 of each of the four corners of the workpiece glass plate 34 is computed (step S28).

Specifically, the radiated (RADized) cabinets r1 to r4 of the corner portions of the work glass plate 34 are calculated using the equations described below, and the work glass plate 34 is further based on the cabinets r1 to r4. The squareness ∠1 to ∠4 of each of the four corners of are calculated.

By the above process, the squareness # 1-# 4 of each of the four corners of the workpiece glass plate 34 is computed, and is stored in the memory | storage means 12b.

Subsequently, the image processing apparatus 12 has the length dimensions E1, E2, ER, EL, and right angles ∠1 to ∠4 and predetermined predetermined standard values (setting ranges) of each of the four sides of the calculated work glass plate 34. ), And based on the comparison result, whether the calculated length dimensions E1, E2, ER, EL and the right angles ∠1 to ∠4 are within a standard value (setting range), that is, the work glass plate 34 The defect determination of the external shape is performed (step S30). And the image processing apparatus 12 is a step S20, if the calculated length dimensions E1, E2, ER, EL and right angles # 1 to # 4 are within a standard value (setting range) (step S30: YES). Returning to, the processing of steps S20 to S30 is repeated for the workpiece glass plate 34 that has reached the measurement section 32 next. That is, the shape measurement of each of the some workpiece glass plate 34 (refer FIG. 3) conveyed on the measurement line 30 is carried out nonstop. On the other hand, the image processing apparatus 12 displays an alarm or the like if the calculated length dimensions E1, E2, ER, EL and the right angles # 1 to # 4 are not within the setting range (step S30: NO). By notifying that, the effect is notified.

As explained above, according to the external shape measuring method of the workpiece glass plate of this embodiment, it arrange | positions corresponding to four corners of the workpiece glass plate 34 previously, without moving the imaging means 18C0-18C3 to XY direction like conventionally. The four image pickup means 18C0 to 18C3 simultaneously or nearly simultaneously to capture an image including the corner portions C1 to C4 of each of the four corners of the work glass plate 34, and the captured images p1 to p4 and the like. Based on it, the external shape (the length dimension of each of the four sides of the workpiece glass plate 34, and the squareness of each of the four corners of a rectangular plate-shaped object) is computed (step S20-S28). For this reason, shape measurement can be performed non-stop about each of the some workpiece glass plate 34 (refer FIG. 3) conveyed on the measurement line 30, and it becomes possible to improve a yield.

Moreover, according to the external shape measuring method of the workpiece glass plate of this embodiment, the workpiece glass plate is used by using the calibration standard glass plate 36 by which the length dimension of each of four sides, and the squareness of each of the four corners were previously measured (known). Calculating the relative coordinates of each of the four imaging means 18C0 to 18C3, which are the basis for the calculation of the outline shape (the length dimension of each of the four sides of the work glass plate 34 and the squareness of each of the four corners) of (34). It becomes possible.

Furthermore, according to the external shape measurement method of the workpiece glass plate of this embodiment, since it comprises step S10 which correct | amends the previously measured squareness of each of the four corners of the standard glass plate 36 for calibration, the standard for calibration measured previously Even if the measurement error was included in the length dimension of each of the four sides of the glass plate 36, and the squareness of each of the four corners, the measurement error will cancel. This makes it possible to calculate the relative coordinates of each of the four imaging means 18C0 to 18C3 with higher accuracy.

Next, the modification is demonstrated.

In the said embodiment, although the example whose measurement object was the four-corner standard glass plate 36 and the workpiece glass plate 34 cut out as shown in FIG. 5 was demonstrated, this invention is not limited to this. For example, CP coordinates C1PX to C4PX, C1PY to C4PY, and four imaging means (4) are similarly used even when the standard glass plate 36 or the work glass plate 34 for which four corners as shown in FIG. 3 are not cut out is used. 18C0 to 18C3) The relative coordinates S0 to S3 of each of the four corners of the four lengths of the four sides of the work glass plate 34 and the four corners of the work glass plate 34 are calculated. It is possible to calculate from # 4.

In addition, in the said embodiment, although the example whose measurement object was the glass plate which passed through the cutting process, the chamfering process, and the washing and drying process was demonstrated, this invention is not limited to this. For example, the glass plate before a cutting process, the glass plate before a chamfering process after a cutting process, and the glass plate before a washing | cleaning and drying process after a chamfering process can also be made into a measurement object.

In addition, although the said embodiment demonstrated the example which calculates the relative coordinates S0-S3 of each of the four imaging means 18C0-18C3 by the process of step S10-S18, this invention is not limited to this. For example, if the relative coordinates S0 to S3 of each of the four imaging means 18C0 to 18C3 are measured in advance, the external shape of the work glass plate 34 is determined by using the relative coordinates S0 to S3 measured in advance. It is possible to measure (steps S20-S32).

In addition, in the said embodiment, although the example in which the rectangular plate-shaped object of a measurement object was a glass plate was demonstrated, this invention is not limited to this. It is also possible to apply similarly to other rectangular plate-like objects, such as a wooden board, a metal board, and a resin board.

The above embodiments are merely examples in all respects. By these description, this invention is not interpreted limitedly. This invention can be implemented in other various forms, without deviating from the mind or main character.

Although this application was detailed also demonstrated with reference to the specific embodiment, it is clear for those skilled in the art that various changes and correction can be added without deviating from the mind and range of this invention.

This application is based on the JP Patent application (Japanese Patent Application No. 2009-035732) of an application on February 18, 2009, The content is taken in here as a reference.

10: shape measuring device
12: image processing apparatus
12a: arithmetic and control means
12b: storage means
14: LED power
16: lighting means
20: sensor
30: measuring line
32: measurement section
34a: end border
36: standard glass plate for calibration
C1-C4: corner

Claims (4)

A rectangle conveyed to pass through a shape measuring section by using a shape measuring device having four imaging means arranged in advance corresponding to four corners of a rectangular plate-shaped object and a storage means for storing relative coordinates of each of the four imaging means. In the measuring method of measuring the external shape of a plate-shaped object,
Determining whether the rectangular plate-like article has reached the measurement section;
In the case where it is determined that the rectangular plate-shaped object has reached the measurement section, photographing an image including corner portions of each of the four corners of the rectangular plate-shaped object having reached the measurement section by the four imaging means;
Calculating corner post coordinates which are coordinate values from an image origin of each of the four corners of the rectangular plate-shaped object on the basis of the captured image;
Calculating length dimensions of each of the four sides of the rectangular plate-shaped object based on the calculated corner post coordinates of the rectangular plate-shaped object and the relative coordinates stored in the storage means;
Calculating a squareness of each of the four corners of the rectangular plate-like object based on the calculated corner post coordinates, the relative coordinates stored in the storage means, and the calculated length dimension.
An external shape measurement method of the rectangular plate-shaped object characterized by including the. The method of claim 1, further comprising: comparing the calculated length dimension and squareness with a predetermined standard value;
Based on the comparison result, a step of performing a defective determination of the external shape of the rectangular plate-shaped object
A method of measuring the external shape of a rectangular plate-shaped object further comprising. The rectangular plate-shaped product according to claim 1 or 2, based on a pre-measured length dimension of each of the four sides of the standard rectangular plate-shaped product for calibration and the measured squareness of each of the four corners of the standard rectangular plate-shaped product for calibration. A step of correcting the pre-measured squareness of each of the four corners,
Photographing an image including corner portions of each of the four corners of the standard rectangular plate-like object for calibration by the four imaging means;
Calculating corner post coordinates of each of the four corners of the standard rectangular plate-like object for calibration, based on the captured image;
Calculate the relative coordinates of each of the four imaging means based on the calculated corner post coordinates of the calibration standard rectangular plate, the corrected squareness, and the measured length dimension of each of the four sides of the calibration standard rectangular plate. And storing in the storage means
A method of measuring the external shape of a rectangular plate-shaped object further comprising. In the method for calibrating the relative coordinates of the four imaging means in the shape measuring device having four imaging means arranged in advance corresponding to four corners of the rectangular plate-shaped object,
Based on the measured length dimension of each of the four sides of the calibration standard rectangular plate and the measured squareness of each of the four corners of the calibration standard rectangular plate, the measured squareness of each of the four corners of the rectangular plate Step to correct,
Photographing an image including corner portions of each of the four corners of the standard rectangular plate-like object for calibration by the four imaging means;
Calculating corner post coordinates of each of the four corners of the standard rectangular plate-like object for calibration, based on the captured image;
Calculate the relative coordinates of each of the four imaging means based on the calculated corner post coordinates of the calibration standard rectangular plate, the corrected squareness, and the measured length dimension of each of the four sides of the calibration standard rectangular plate. Step
And a relative position of the imaging means.

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